One of my twitter account was finally indexed on the 2nd serp page for a very popular keyword the other day. Then yesterday, I noticed that it vanished and then today learned that it's no longer indexed at all in Google. Any possible explanations as to what might have caused this? Thanks.
Well this one did. And although some of the post pages are still there, the homepage clearly dropped from the serps.
I think the twitter was get index for popular keywords because you use keywords on your update. We know that google loves fresh update that is why I'n thinking it's just because of an update.
It's true that I insert the targeted keyword into my posts. Are you saying that this is an update and it will reappear or that it will go away for good?
All Twitter data is crawled and indexed as real time search results. Google is keeps this real time index fresh and makes sure all stale data is de indexed timely, this is only for real time index.
Did you made a lot of backlinks for you twitter account? Google loves twitter and your case is so strange.